The present invention relates generally to a formulation which is adapted for application to dry wall surfaces, and also for the jointing and filling of dry wall panels. The formulation has excellent adhesive and cohesive properties, and is specifically designed for adhering to gypsum dry wall panels. The binder or film-forming material is internally plasticized so as to provide durability, resistance to cracking, checking, or other such failures over extended periods of time.
In the building industry, dry wall construction is being widely used due to its ease of application, versatility, and lack of extended drying or curing times frequently encountered when wet plaster finishes are contemplated. Dry wall panels utilize a gypsum core with a finish or outer coating of fiberboard or the like. Dry wall panels are, of course, widely commercially available.
In conventional construction, dry wall panels are mounted onto unfinished walls, and thereafter are treated so as to cover or fill the joint existing between adjacent panels. Presently, a hydrosettable filler is normally utilized, with these materials always requiring a taping layer to be applied thereover so as to reduce the tendency of the filler material to crack upon drying. Some such materials cure at least partially through evaporation of water. Shrinkage of the normal filler material will inherently occur, and after extended periods of time, cracks appear in the joint area.
A further disadvantage in the conventional jointing and filling of dry wall panels is the requirement that the joint area receive multiple layers or coatings, with the final coating requiring sanding so as to smooth the appearance of the joint. Such operations are, of course, required in order to conceal recessed nails which are normally, at least in the joint area, driven into the panel with a crushing blow. The area surrounding the nail head is frequently indented by the final blow of the hammer, and hence these areas must be covered in order to render the wall surface more smooth and sightly.
Following the application of the jointing and filling compound, the surface of the dry wall panels is ready to receive a coat of paint, as required or desired.
The dry wall industry has had a long-felt need for a jointing and filling compound which is easily applied, and which does not require the utilization of a tape to avoid the cracking tendency. Furthermore, any such formulation which would not require taping would also desirably be sandable to a degree.
Dry wall panels normally have edge surfaces which are tapered inwardly along the outside surface. This tapering or "feathering" is provided in order to accommodate a jointing and filling compound, along with the conventional tape. The formulation of the present invention has excellent adhesive and cohesive properties, thereby permitting the material to be applied to the dry wall panel surface in relatively thin layers.
In addition to use as a dry wall filler and jointing compound, the formulations of the present invention may also be utilized as a coating, either in smooth or textured form. In other words, the formulations may be modified only slightly, such as by increased or decreased use of water so as to enable the formulation to be utilized as a jointer and filler material, and thereby applied with a conventional trowel or knife, or alternatively, as a wall surface coating and accordingly applied with a conventional paint roller or brush as desired.